Heat dissipation apparatus and frame thereof

ABSTRACT

An exemplary heat dissipation apparatus includes frame, a cooling fan and a heat sink. The frame includes an annular wall, a supporting board extending inward from a top of the annular wall, a plurality of legs extending downwardly from a bottom of the annular wall, and a plurality of engaging portions extending inward from an inner circumferential surface of the annular wall. A bottom of each engaging portion forms a plurality of steps at different levels. The levels of the steps of each engaging portion correspond to the levels of the steps of each other engaging portion. The cooling fan is arranged on the supporting board of the frame. The heat sink abuts against one of the steps of each engaging portion.

BACKGROUND

1. Technical Field

The present disclosure relates generally to heat dissipation apparatuses, and more particularly relates to a frame of a heat dissipation apparatus which is adapted for fixing the heat dissipation apparatus to a heat-generating component.

2. Description of Related Art

With the continuing development of electronics technology, electronic components of electronic devices, such as central processing units (CPUs), memory modules, and video graphics array (VGA) chips, generate much heat which needs to be dissipated immediately.

Generally, heat sinks combined with cooling fans are used for dissipating heat of such electronic components, to ensure the continued proper functioning of the electronic device. However, the electronic components are of various sizes, and thus the heat sinks usually have different heights. Each type of heat sink needs a special frame for securing the heat sink and the fan to the electronic component. Thus, a number of different heat sinks and frames are needed, which adds to the cost of the electronic device.

What is needed, therefore, is a heat dissipation apparatus with a frame to overcome the above-described limitations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric, assembled view showing a heat dissipation apparatus according to an exemplary embodiment in use.

FIG. 2 is an exploded view of FIG. 1.

FIG. 3 is an inverted view of a frame of the heat dissipation apparatus shown in FIG. 2.

FIG. 4 is a bottom plan view of the assembled heat dissipation apparatus of FIG. 1.

FIG. 5 is similar to FIG. 4, but shows an assembled heat dissipation apparatus according to an alternative embodiment.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, a heat dissipation apparatus according to an exemplary embodiment is shown. In this embodiment, the heat dissipation apparatus is applied for dissipating heat of an electronic component 42 of an electronic device (not shown). The electronic component 42 is arranged on a circuit board 40. A plurality of apertures 44 are defined in the circuit board 40 around the electronic component 42, for securing the heat dissipation apparatus onto the electronic component 42.

The heat dissipation apparatus includes a heat sink 10 attached to the electronic component 42, a cooling fan 30 arranged on the heat sink 10, a frame 20 sandwiched between the heat sink 10 and the cooling fan 30, and a plurality of fasteners 100 extending through the frame 20 and respectively engaging in the apertures 44 of the circuit board 40. In this embodiment, there are four apertures 44 defined in the circuit board 40, and four fasteners 100 are provided for securing the heat dissipation apparatus. In other embodiments, the number of apertures 44 and the number of fasteners 100 can be changed according to need.

The heat sink 10 in general has a cylindrical-shaped profile. The heat sink 10 includes a core 12, a plurality of fins 14, a plurality of engaging arms 16, and a plurality of positioning arms 18. The core 12 is solid and cylindrical. Referring also to FIG. 4, a bottom surface 120 of the heat sink 10 is circular, and configured for contacting the electronic component 42. All of the fins 14, the engaging arms 16, and the positioning arms 18 curve outward from an outer circumferential surface of the core 12 generally toward a clockwise direction as viewed in FIGS. 1-2. In this embodiment, there are two positioning arms 18 and two engaging arms 16 formed on the heat sink 10. The positioning arms 18 and the engaging arms 16 are arranged in an alternating fashion around the outer circumferential surface of the core 12. The positioning arms 18 are generally symmetrical relative to each other about a central axis of the core 12, and the engaging arms 16 are generally symmetrical relative to each other about the central axis of the core 12.

In this embodiment, a thickness of each of the positioning arms 18 and each of the engaging arms 16 is considerably greater than that of each of the fins 14. A groove 160 is defined at an outer end of each engaging arm 16 which is farthest away from the core 12. The groove 160 is elongated, and extends through the top edge and bottom edge of the engaging arm 16 along a direction parallel to the central axis of the core 12. Some of the fins 14 near each of the positioning arms 18 and each of the engaging arms 16 have smaller widths than the other fins 14, each width being measured in an essentially radial direction from the outer circumferential surface of the core 12. More specifically, some of the fins 14 at each of two lateral sides of each engaging arm 16 have smaller widths, while some of the fins 14 at one lateral side only of each positioning arm 18 have smaller widths. In this description, unless the context indicates otherwise, a fin 14 with a smaller width is referred to as a “shorter” fin 14.

The cooling fan 30 includes a fan housing 32, and an impeller 36 rotatably received in the fan housing 32. The fan housing 32 has a rectangular-shaped profile. A cylindrical-shaped space is defined in the fan housing 32, the space receiving the impeller 36 therein. A mounting hole 340 is defined in each corner 34 of the fan housing 32, for securing the cooling fan 30 to the frame 20.

The frame 20 is integrally formed by plastic. That is, the frame 20 is a single, one-piece, monolithic body of the same material without any internal seams. The frame 20 includes an annular wall 22, which has an inner diameter substantially the same as an outer diameter of the heat sink 10. A supporting board 24 extends inward from a periphery of a top of the annular wall 22, for supporting the cooling fan 30 thereon. An opening 240 is defined in a central portion of the supporting board 24, for air to flow therethrough to the heat sink 10. In this embodiment, the opening 240 is generally rectangular, and is slightly smaller than the fan housing 32 of the cooling fan 30.

A plurality of ears 26 extend outward from the top of the annular wall 22. Top sides of the ears 26 and the supporting board 24 are coplanar. In this embodiment, there are four ears 26 formed corresponding to the four corners 34 of the fan housing 32. A pole 260 extends perpendicularly upwardly from each of the ears 26. The pole 260 is slightly larger than the mounting hole 340 in diameter. A hook 262 extends upwardly from each ear 26, for clasping the corresponding corner 34 of the fan housing 32. The hook 262 is arranged adjacent to the pole 260.

A plurality of legs 28 extend downwardly from a bottom of the annular wall 22. In this embodiment, there are four legs 28 evenly arranged along a circumferential direction of the annular wall 22. Each leg 28 is generally L-shaped. A through hole 280 is defined in a bottom of each leg 28, corresponding to a respective one of the apertures 44 of the circuit board 40. A protrusion 282 protrudes inward from an inner surface of each leg 28. The protrusions 282 of the legs 28 are substantially at the same level.

Referring also to FIG. 3, a plurality of engaging portions 25 and a plurality of positioning portions 29 protrude inward from an inner circumferential surface 220 of the annular wall 22. The engaging portions 25 and the positioning portions 29 are arranged in an alternating fashion, and are evenly distributed along the circumferential direction of the annular wall 22. In this embodiment, there are two engaging portions 25 formed corresponding to the two engaging arms 16 of the heat sink 10, and two positioning portions 29 formed corresponding to the two positioning arms 18 of the heat sink 10. It should be understood that in a variety of embodiments, the number of engaging portions 25 varies according to the number of engaging arms 16, and the number of positioning portions 29 varies according to the number of positioning arms 18.

Each of the engaging portions 25 includes a top side connected to the supporting board 24, and a step-shaped bottom side. In this embodiment, the bottom side of each engaging portion 25 includes in sequence a first step 250, a second step 252 and a third step 254 along the clockwise direction as viewed in FIG. 2. The first step 250, the second step 252 and the third step 254 are planar, and are parallel to each other. The third step 254 is slightly higher than the bottom of the annular wall 22, the second step 252 is slightly higher than the third step 254, and the first step 250 is slightly higher than the second step 252. In other words, the second step 252 is closer to the bottom of the annular wall 22 than the first step 250, while the third step 254 is closer to the bottom of the annular wall 22 than the second step 252.

A first rib 251 extends perpendicularly downwardly from a middle of the first step 250 of each engaging portion 25, a second rib 253 extends perpendicularly downwardly from a middle of the second step 252 of each engaging portion 25, and a third rib 255 extends perpendicularly downwardly from a middle of the third step 254 of each engaging portion 25. The first rib 251, the second rib 253, and the third rib 255 of each engaging portion 25 are parallel to, and spaced from, each other. Each of the first ribs 251, the second ribs 253, and the third ribs 255 is column-shaped, and has a diameter substantially the same as that of the groove 160 of each engaging arm 16 of the heat sink 10. Bottom ends of the first ribs 251, the second ribs 253 and the third ribs 255 are coplanar with the bottom of the annular wall 22. In the illustrated embodiment, the first, second and third ribs 251, 253, 255 are integrally formed with the annular wall 22. That is, in one sense, the first, second and third ribs 251, 253, 255 are elongated structures protruding from the inner circumferential surface of the annular wall 22.

Each of the positioning portions 29 includes a top surface connected to the supporting board 24, and a step-shaped bottom surface. In this embodiment, the bottom surface of each positioning portion 29 includes in sequence a first step 290, a second step 292 and a third step 294 along the clockwise direction as would be viewed in FIG. 2. The first steps 290 of the positioning portions 29 are substantially coplanar with the first steps 250 of the engaging portions 25, the second steps 292 of the positioning portions 29 are substantially coplanar with the second steps 252 of the engaging portions 25, and the third steps 294 of the positioning portions 29 are substantially coplanar with the third steps 254 of the engaging portions 25.

Referring to FIG. 1 again, when the heat dissipation apparatus is assembled, the frame 20 is arranged on the top of the heat sink 10, and the cooling fan 30 is arranged on the supporting board 24 of the frame 20, with the poles 260 respectively extending through the mounting holes 340 of the fan housing 32 by interference fit. The hooks 262 each grasp a periphery of the corresponding corner 34 of the fan housing 32. Thus, the cooling fan 30 is secured to the frame 20. Since the frame 20 has the step-shaped engaging portions 25 and positioning portions 29, the frame 20 can be applied to different types of heat sinks with different heights. More specifically, in this embodiment, each of the engaging portions 25 has the three steps 250, 252, 254 at different levels, and each of the positioning portions 29 has the three steps 290, 292, 294 corresponding to the steps 250, 252, 254 of the engaging portions 25. Thus the frame 20 can accommodate any of three different heat sinks therein.

Referring to FIG. 4, the heat sink 10 has a relatively low height. Accordingly, when the frame 20 is disposed on the heat sink 10, it is the third ribs 255 of the engaging portions 25 that are aligned with the grooves 160 of the engaging arms 16 of the heat sink 10, respectively. Then the frame 20 is pressed to move downwardly to cause the third ribs 255 to respectively enter the grooves 160 of the engaging arms 16. Thus the frame 20 can move downwardly until the third steps 254 contact the top edges of the engaging arms 16. In such a state, the third steps 294 of the positioning portions 29 contact top edges of the positioning arms 18, and the protrusions 282 of the legs 28 abut bottom edges of corresponding fins 14. Thus axial movement of the heat sink 10 is limited. Further, the third ribs 255 of the frame 20 engaged in the grooves 160 of the engaging arms 16 limit rotation of the heat sink 10 relative to the frame 20. Therefore, the heat sink 10 is stably attached to the frame 20 to form the heat dissipation apparatus. The combined frame 20 and heat sink 10 provide the heat dissipation apparatus with a given height.

FIG. 5 shows an alternative heat sink 50 attached to the frame 20. In this embodiment, the heat sink 50 is the same as the heat sink 10 of the previous embodiment, except that the heat sink 50 has a relatively great height. The heat sink 50 includes a pair of engaging arms 56 and a pair of positioning arms 58. Each engaging arm 56 defines a groove 560 therein. In assembly, the frame 20 is disposed on the heat sink 50, with the first ribs 251 aligned with the grooves 560. Then the frame 20 is moved downwardly until the first steps 250 of the engaging portions 25 contact the top edges of the engaging arms 56, and the first steps 290 of the positioning portions 29 contact top edges of the positioning arms 18. Similarly, the protrusions 282 of the legs 28 abut bottom edges of corresponding fins (not labeled) of the heat sink 50, to avoid dislodgement of the heat sink 50 from the frame 20. Further, the first ribs 251 of the engaging portions 25 of the frame 20 engaged in the grooves 560 of the engaging arms 56 limits rotation of the heat sink 50 relative to the frame 20. Therefore, the heat sink 50 is stably attached to the frame 20 to form a heat dissipation apparatus. The combined frame 20 and heat sink 50 provide the heat dissipation apparatus with a given height. Such height is substantially the same as the height of the heat dissipation apparatus constituted by the combination of the frame 20 and heat sink 10.

Still another alternative heat sink (not shown) with a suitable height can be provided. Such heat sink is the same as the heat sinks 10, 50 of the previous embodiments, except that said such heat sink is higher than the heat sink 10 and lower than the heat sink 50. Said such heat sink can be attached to the frame 20 to contact the second steps 252 of the engaging portions 25 and the second steps 292 of the positioning portions 29. Thereby, said such heat sink is stably attached to the frame 20 to form a heat dissipation apparatus. The combined frame 20 and said such heat sink provides the heat dissipation apparatus with a given height. Such height is substantially the same as the height of the heat dissipation apparatus constituted by the combination of the frame 20 and heat sink 10, and substantially the same as the height of the heat dissipation apparatus constituted by the combination of the frame 20 and heat sink 50.

As described above, the frame 20 has the steps 250, 252, 254 at different levels. Accordingly, different heat sinks can be attached to the frame 20 to engage with different of the steps 250, 252, 254, respectively. A height of the heat dissipation apparatus obtained is not increased even when a higher heat sink is adopted. Therefore, the frame 20 is essentially all-purpose. In addition, during assembly of the heat sink 10 (50), the shorter fins 14 near the engaging arms 16 (56) and the positioning arms 18 (58) avoid interference between the outer ends of the fins 14 and the engaging portions 25 and positioning portions 29. This makes assembly of the heat sink 10 (50) easier.

When the heat sink 10 (50) and the cooling fan 30 are assembled together by the frame 20, the heat dissipation apparatus is a single, stable assembly, which can be installed onto the electronic component 42 for cooling. When installing the heat dissipation apparatus, the bottom surface 120 of the core 12 of the heat sink 10 (50) is disposed on the electronic component 42, and the through holes 280 of the legs 28 of the frame 20 are aligned with the apertures 44 of the circuit board 40. The fasteners 100 are respectively extended through the through holes 280 to engage in the apertures 44 of the circuit board 40. Thereby, the heat dissipation apparatus is attached to the electronic component 42. During operation, heat generated by the electronic component 42 is transferred to the heat sink 10, and then taken away to an outside environment by the airflow driven by the cooling fan 30.

It should be understood that in alternative embodiments, the frame 20 can have more or fewer steps to suit more or fewer different heat sinks.

It is to be further understood that even though numerous characteristics and advantages of certain embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. A heat dissipation apparatus, comprising: a heat sink comprising a core and a plurality of fins arranged around the core; and a frame disposed on the heat sink, the frame comprising an annular wall, and a plurality of engaging portions protruding inward from an inner circumferential surface of the annular wall, a bottom side of each engaging portion facing the heat sink forming a plurality of steps at different levels, the levels of the steps of each engaging portion corresponding to the levels of the steps of each other engaging portion, the heat sink engaging with one of the steps of each engaging portion.
 2. The heat dissipation apparatus of claim 1, wherein the steps of each engaging portion are arranged in sequence along a circumferential direction of the annular wall.
 3. The heat dissipation apparatus of claim 2, wherein heights of the steps of each engaging portion gradually decrease along the circumferential direction of the annular wall.
 4. The heat dissipation apparatus of claim 1, wherein the heat sink defines a groove corresponding to each engaging portion, a rib extends perpendicularly downwardly from each of the steps of each engaging portion, and one of the ribs which extends from said one of the steps of each engaging portion with which the heat sink is engaged is received in the corresponding groove of the heat sink.
 5. The heat dissipation apparatus of claim 4, wherein the heat sink further comprises a plurality of engaging arms arranged around the core, the grooves being respectively defined at an outer ends of the engaging arms which are farthest away from the core.
 6. The heat dissipation apparatus of claim 5, wherein some of the fins adjacent to each engaging arm are shorter than other fins as being measured in a generally radial direction from an outer circumferential surface of the core of the heat sink.
 7. The heat dissipation apparatus of claim 1, wherein a plurality of legs extend downwardly from a bottom of the annular wall, a through hole being defined in each leg for fixing of the heat dissipation apparatus to an object.
 8. The heat dissipation apparatus of claim 7, wherein a protrusion extends inward from an inner surface of each leg, the protrusions engaging with a bottom of the heat sink to avoid dislodgement of the heat sink from the frame.
 9. The heat dissipation apparatus of claim 1, wherein a supporting board extends inward from a top of the annular wall for supporting a fan thereon, the supporting board defining an opening at a central portion thereof for allowing air to flow therethrough to the heat sink.
 10. The heat dissipation apparatus of claim 9, wherein a plurality of ears extends outward from the top of the annular wall, a pole extending upwardly from each ear for engaging with the fan.
 11. The heat dissipation apparatus of claim 9, wherein a plurality of ears extends outward from the top of the annular wall, a hook extending upwardly from each ear for clasping one corner of the fan.
 12. A heat dissipation apparatus, comprising: a frame comprising an annular wall, a supporting board extending inward from a top of the annular wall, a plurality of legs extending downwardly from a bottom of the annular wall, and a plurality of engaging portions extending inward from an inner circumferential surface of the annular wall, a bottom of each engaging portion forming a plurality of steps at different levels, the levels of the steps of each engaging portion corresponding to the levels of the steps of each other engaging portion; a cooling fan arranged on the supporting board of the frame; and a heat sink abutting against one of the steps of each engaging portion.
 13. The heat dissipation apparatus of claim 12, wherein the heat sink comprises a cylindrical-shaped core, a plurality of fins and a plurality of engaging arms corresponding to the plurality of engaging portions of the frame, the fins and engaging arms being arranged around the core, each engaging arm defining a groove at an outer end thereof farthest away from the core.
 14. The heat dissipation apparatus of claim 13, wherein a rib extends downwardly from each of the steps of the engaging portion, one of the ribs extending from the one of the steps the heat sink abutting against being received in the groove of one corresponding engaging arms.
 15. The heat dissipation apparatus of claim 12, wherein a plurality of ears extends outward from the top of the annular wall, a pole extending upwardly from each ear and engaging with the fan, and a hook extending upwardly from each ear and clasping one corner of the fan.
 16. The heat dissipation apparatus of claim 12, wherein a protrusion extends inward from an inner surface of each leg, the protrusions engaging with a bottom of the heat sink to avoid dislodgement of the heat sink from the frame.
 17. A frame adapted for fixing a heat dissipation apparatus in position relative to an object, the frame comprising: an annular wall; a plurality of legs extending outward from one end of the annular wall, each of the legs defining a through hole therein; and a plurality of engaging portions extending inward from an inner circumferential surface of the annular wall, a side of each engaging portion facing toward the legs forming a plurality of steps at different levels, the levels of the steps of each engaging portion corresponding to the levels of the steps of each other engaging portion.
 18. The frame of claim 17, wherein a rib extends perpendicularly from each of the steps of the engaging portion, for engaging with a heat sink of the heat dissipation apparatus.
 19. The frame of claim 17, wherein a protrusion extends inward from an inner surface of each leg, for engaging with a heat sink of the heat dissipation apparatus.
 20. The frame of claim 17, wherein a supporting board extends inward from another end of the annular wall farthest from the legs, the supporting board is adapted for supporting a fan of the heat dissipation apparatus, a plurality of ears extends outward from the another end of the annular wall, a pole extends perpendicularly outward from each ear for engaging with the fan, and a hook extends perpendicularly outward from each ear for clasping a frame of the fan. 